Carbon sequestration is a topic receiving enormous attention in the media and among government agencies and industries involved in fuel production and use. Combustion of fossil fuels is responsible for approximately 83% of greenhouse gas emissions in the U.S. Currently, the U.S. emits 6.0×109 tons carbon dioxide per year and this value is expected to increase by 27% over the next 20 years. Furthermore, the reported link between increasing concentrations of greenhouse gases such as carbon dioxide (CO2) in the atmosphere and global climate change has prompted several countries to adopt environmental standards that cap CO2 emissions and aim to reduce current emissions. In April 2007, the U.S. Supreme Court ruled that carbon dioxide was a pollutant and that the U.S. Environmental Protection Agency (U.S. EPA) has the authority and obligation to regulate carbon dioxide emissions. The U.S. EPA has decided that carbon dioxide poses a threat to human health and the environment and that it will now be added to a list of 5 other greenhouse gases that can be regulated under the Clean Air Act. It is expected that the federal government may eventually enact a carbon cap-and-trade bill. When this occurs, utility companies, coal producers, and other industrial carbon dioxide emitters are in a position to be particularly affected by federal carbon dioxide regulation due to a large carbon dioxide footprint. An objective of the present invention may be to turn carbon dioxide into a valued resource rather than a costly expense and a liability. Embodiments of the present invention have applications in carbon dioxide capture for industrial carbon dioxide emitters, including fuel conversion sources, coal-fired power plants, natural gas-fired power plants and perhaps even distributed generation fuel cells, as well.
Most biological carbon capture and re-use technologies rely on photosynthetic microorganisms for the carbon capture. The biological techniques have been investigated since the 1970s and are now implemented at pilot-scale for carbon dioxide capture and conversion to biomass. Although algae-based technologies have shown potential for carbon dioxide capture, these technologies may be limited by the large land area that is required for adequate light penetration for optimal photosynthesis and carbon uptake rates in open ponds or by the cost of photobioreactors. These obstacles, however, may be overcome by the bacterial reactor system in the various embodiments of the present invention.
The present invention may include a Chemoautotrophic (“CAT”) bacteria-based CO2 consuming process for the production of biodiesel and other bio-based products. The CAT process can provide industrial carbon dioxide emitters and others with a carbon capture and re-use technology that may produce salable products perhaps thereby turning an environmental hazard and expense (such as a greenhouse gas “GHG”) into a resource. If all power plant CO2 emissions are converted to biodiesel such as perhaps to about 64 billion barrels of biodiesel, then the domestic transportation fuel market could be well supplied. Power plant efficiency can improve with minimal impact on the cost of electricity.